If you already have the old one off take it into O'Reilly and tell them I want to order one of these. They will ask what it is off of. Tell them year make model and point out the lug to them. Then they will order it to the store. When you go to pick it up again bring in the old one and inspect it before leaving the store. If it does not have the lug tell them, this is not going to fit, and point out why. They will take it back.

As for NAPA, they are really hit or miss because most stores are independently owned. The advantage of NAPA is because of the business model it is cheep enough that most small towns can put one in. The disadvantage is they have to mark the prices up more for the owner to make any money at all. The other disadvantage is because many of these owners are not understanding that it is good to try to win repeat customers they can have bad business practices. Because of this I would not avoid all business with all NAPAs because of bad experience with one NAPA. I would not go back to that one NAPA. I use NAPA only in rural areas where it would cost more to drive to a different part store than to buy at the inflated price. And I only buy parts that I know they will get right. But if you are really concerned about getting the correct one I have had success with some online parts stores having more and better pictures.